If the mean of 4 observations is 20, when a constant 'c' is added to each observation, the mean becomes 22. The value of…

When the average age of a couple and their son was 42 years, the son married and got a child after one year. When the ch…

The average age of four brothers is 12 years. If the age of their mother is also included, the average is increased by 5…

The mean of 5 numbers is 18. If one number is excluded, their mean is 16. Find the excluded number.

In a class, there are 40 boys and their average age is 16 years. One boy, aged 17 years, leaving the class and another j…

A certain factory employed 600 men and 400 women and the average wage was Rs. 25.50 per day. If women got Rs. 5 less tha…

The average age of mother and her six children is 12 years, which is reduced by 5 years if the age of mother is excluded…

The average mark of student in 4 subjects is 75. If the student obtained 80 marks in the fifth subject, then the new ave…